The objectives of this study are to estimate the extent of cocaine abuse among pregnant women in New York City and to investigate its effect on pregnancy and health of the newborn. Two independent epidemiologic study components are proposed. A prospective component will identify women who attend their first prenatal visit before 24 completed weeks gestation and will provide a description of the frequency and patterns of cocaine abuse in this population. The relationship between patterns of cocaine abuse and third trimester obstetric events, complications of delivery, and adverse neonatal outcomes will be examined by comparing women who have used cocaine during pregnancy (exposed cohort) with two unexposed cohorts. One unexposed cohort, the "drug free lifestyle" group, will consist of women who do not use drugs and do not have partners who use drugs. The other unexposed cohort, the "cocaine lifestyle" group, will consist of women who do not use cocaine but have male partners who do and thus may experience life circumstances similar to that of the exposed cohort. A restrospective, case-control component will look at the relationship between preterm delivery and cocaine abuse among women who have not received prenatal care before 24 completed weeks gestation. The frequency of recent cocaine use among cases (women who deliver before 36 completed weeks gestation) will be compared with that among controls (women who deliver after 36 completed weeks gestation). The study will take place in two hospitals in Northern Manhattan where cocaine use has reached an epidemic level. Six-hundred patients will be recruited for the prospective component and 500 patients will be recruited for the retrospective component.